Electrostatic discharge (ESD) is a sudden and typically unintended increase in current caused by the introduction of an electrical charge that creates an electric potential that is greater than the operating voltage of a circuit. Damage to the materials that comprise the components of the circuits can occur if the current flow is excessive. ESD events can cause minor interruptions in circuit operations which are recoverable and do not cause permanent damage to the devices. But, if the current flow exceeds a materials capability to function as a dielectric or insulator and begins to conduct current freely, then unrecoverable damage may occur and render a circuit inoperative. Prevention of ESD damage may comprise charge dissipation techniques that include anti-static materials, grounding devices, deionizers, or fuses.
Electromagnetic interference (EMI) is a sudden increase in current in a transistor or circuit caused by the propagation of electromagnetic energy from a source in proximity to the transistor or circuit. Electromagnetic compatibility (EMC) is the study of various techniques to reduce or eliminate EMI by grounding or shielding susceptible transistors or circuits or suppressing EMI sources to minimize the impact on nearby transistor and circuits. For example, fuses, filters, or switches may be used to minimize the impact of EMI.